Bug in Graham Scan Convex Hull.cpp

[lxxue]

I guess there is a bug in the implementation of Graham's Scan algorithm.

Try the following testcase:
Input: { 0, 0 }, { 1, 1 }, { 2, 2 }, { 1, 4 }
output: { 1, 4 }, { 2, 2 }, { 1, 1 }, { 0, 0 }
correct output: { 1, 4 }, { 2, 2 }, { 0, 0 }

I believe the problem is in line 70: points[1] is not necessarily a vertex of convex hull if points[1] and points[2] have the same direction.

Btw: thank you for your wonderful blogs and readable code!

[avighnac]

Yeah, the convex hull code doesn't even pass on CSES, like bruh.